Schneider Electric ATS48 Soft Starter Modules – ATS48C11Q

Technical Dossier

Product Details And Specifications

Schneider Electric ATS48 Series Technical Notes

The Evolution of ATS48 Architecture

The ATS48 platform was introduced in the late 1990s as a successor to the Altistart 46 (ATS46) series, incorporating closed-loop torque control in place of open-loop voltage ramp. The core architecture uses six SCR (thyristor) pairs in a fully anti-parallel configuration, enabling both soft start and soft stop with motor current feedback. Early firmware revisions (pre-2005) supported only basic current limiting and voltage ramp modes. From 2005 onward, embedded motor thermal protection (class 10/20/30), PTC thermistor input, and fieldbus readiness via the integrated Modbus RTU port became standard. The ATS48 communicates natively at 19,200 baud over RS-485 and supports optional communication cards for CANopen, DeviceNet, Profibus DP, and Ethernet/IP — making it compatible with Schneider Modicon M340, Premium, and Quantum PLC architectures as well as third-party DCS platforms. Units manufactured before 2010 use a discrete gate driver board (VW3A58101) that is now a controlled spare; post-2012 revisions integrated the gate drive onto the main power board, reducing component count. The ATS48 series reached end-of-active-production in most current ratings by 2020, with Schneider Electric designating the Altivar Soft Starter ATS480 as the direct replacement platform. However, the ATS48 remains in active service across thousands of installed sites, and replacement units, repaired modules, and compatible spare boards continue to be sourced through specialist distributors.

ATS48 Full Catalog & Functionalities (SKU List)

The following SKUs represent the verified production range of the ATS48 series, classified by current rating and form factor. All units are three-phase, 208–690 V AC input unless otherwise noted.

ATS48D17Q: 17 A / 7.5 kW at 400 V — entry-level soft starter, DIN rail or panel mount, standard bypass contactor required.
ATS48D22Q: 22 A / 11 kW at 400 V — compact body, integrated motor thermal protection class 10/20/30.
ATS48D32Q: 32 A / 15 kW at 400 V — supports tachometer feedback input for closed-loop speed ramp.
ATS48D38Q: 38 A / 18.5 kW at 400 V — standard industrial frame, Modbus RTU integrated.
ATS48D47Q: 47 A / 22 kW at 400 V — suitable for centrifugal pump and fan applications.
ATS48D62Q: 62 A / 30 kW at 400 V — mid-range frame, supports inside-delta (6-wire) connection.
ATS48D75Q: 75 A / 37 kW at 400 V — inside-delta capable, extended thermal memory on power cycle.
ATS48C11Q: 110 A / 55 kW at 400 V — heavy industrial frame, forced-air cooling recommended above 45°C ambient.
ATS48C14Q: 140 A / 75 kW at 400 V — dual fan cooling, integrated ground fault detection option.
ATS48C17Q: 170 A / 90 kW at 400 V — high-inertia load profile, extended soft stop ramp up to 60 s.
ATS48C21Q: 210 A / 110 kW at 400 V — large frame, supports external bypass for continuous duty cycle.
ATS48C25Q: 250 A / 132 kW at 400 V — process industry standard, compatible with VW3A58202 communication card.
ATS48C32Q: 320 A / 160 kW at 400 V — requires external line contactor; internal bypass rated for 320 A continuous.
ATS48C41Q: 410 A / 200 kW at 400 V — compressor and crusher duty, dual PTC input channels.
ATS48C48Q: 480 A / 250 kW at 400 V — high-power frame, forced ventilation mandatory, IP00 enclosure.
ATS48C59Q: 590 A / 315 kW at 400 V — requires dedicated MCC cubicle, external current transformers for metering.
ATS48C66Q: 660 A / 355 kW at 400 V — refinery and offshore platform standard, UL508 listed variant available.
ATS48C79Q: 790 A / 400 kW at 400 V — large motor starting, compatible with Modicon Quantum safety PLC interlock.
ATS48M10Q: 1000 A / 500 kW at 400 V — mega-frame, water-cooled thyristor stack option available.
ATS48M12Q: 1200 A / 630 kW at 400 V — maximum standard rating, nuclear auxiliary and LNG compressor applications.

Sourcing Hard-to-Find & Obsolete ATS48 Parts

DriveKNMS supports installed-base sourcing for this series through RFQ review, including model matching, condition checks and documentation requirements before quotation.

Quality Control for the ATS48 Range

Each ATS48 unit processed by DriveKNMS undergoes a structured test protocol specific to the thyristor-based soft starter architecture. The test sequence includes: (1) dielectric withstand test at 2.5 kV AC for 1 minute across all power terminals to PE; (2) SCR forward and reverse blocking voltage verification using a calibrated curve tracer; (3) gate trigger current and latching current measurement for each thyristor pair; (4) control board power supply rail verification (±15 V, +5 V logic rails); (5) Modbus RTU communication loop test at 19,200 baud using a reference PLC simulator; (6) full motor simulation run using a resistive load bank at 25%, 50%, and 100% of rated current with soft start ramp verification; (7) thermal imaging of power connections and thyristor heatsinks under load. Units with SCR leakage current exceeding 10 mA at rated blocking voltage are rejected. Fan assemblies are tested for airflow volume and bearing noise. All test data is logged and retained for 5 years.